Felt like it was time for the Atlantic Hurricane Season thread to start up, as Invest 92L in the Gulf of Mexico has been designated Potential Tropical Cyclone Two by the NHC and is rapidly getting its act together. A lot of worried folks in Louisiana tonight and New Orleans in particular - while this storm isn't forecast to have enough time for development into a major hurricane (with the notable exception of the HWRF model, which keeps it out to sea long enough to intensify up to Category 3 before landfall), the Mississippi River is at a very high level and as such, the possibility of a major rain event accompanying this storm could combine with the already high water level and cause severe flooding.

A state of emergency has been declared in Louisiana on account of this threat.

The low is centred just on the fringe of a warm gyre now but will move away from it over the next few hours. A little further south could have made it more potent. Apparently one of the models (the HWRF, I think) went off its head and had it a sub-880 hPa 320 mph beast, but that's been reigned back now.

The low is centred just on the fringe of a warm gyre now but will move away from it over the next few hours. A little further south could have made it more potent. Apparently one of the models (the HWRF, I think) went off its head and had it a sub-880 hPa 320 mph beast, but that's been reigned back now.

I tell a lie. It was with typhoon Mangkut that it went crazy. 866 hPa, 350 mph.

Luckily it seems Barry will quicjly dissipate inland and move off northeast after landfall, limiting the total rainfall. Still, rivers are already quite high along parts of the Gulf Coast so Barry's doing them no favours.

Barry has been named now as max sustained winds are now 35 knots. Some dry air and moderate shear is affecting it, which might be why the 18UTC SHIPS model is not forecasting any intensification of note, however the 15UTC NHC discussion had it just reaching 65 kts (Cat 1) before landfall in 36 hours. In any case it's the rain that's the problem, not the wind.

Barry is being affected by northerly shear, and water vapor imagery indicates mid- to upper-level dry air moving into the cyclone from the northeast. Some moderate shear is now expected to persist until the cyclone makes landfall. Despite this less than ideal environment, the guidance forecasts slow but steady intensification, so the NHC forecast follows this trend. The new intensity forecast is similar to the previous one in calling for Barry to become a hurricane just before landfall in Louisiana, and it lies between the HCCA and ICON consensus models.

Barry is still struggling to take on an appearance even remotely resembling a tropical system, with dry air completely choking the centre. It's more like a sub-tropical hybrid. The latest official forecast has a reduced chance of it reaching hurricane strength before landfall, and by the looks of it the storm total rainfall amounts may be less than feared.

National Hurricane Centre saying Barry set to increase strength until landfall and become classified as a Cat 1 Hurricane briefly before steadily weakening overland and decay to a remnant low within 72hrs. The fact that it is so slow moving is the problem dropping so much rain .

The main area of convection's cloudtops have been warming steadily the past couple of hours, which could be due to proximity to land. It only just crept to hurricane status, despite no actual observations of 65+ kts.

Doesn't seem to be very windy at all in that video. That surface has blown off but it doesn't take a strong wind to do something like that if it's already in a weakened state. A gale gust getting under it and it will act like a sail. Even the guys seem surprised it's failed.

The highest winds on land so far have only been in the 40-45-kt range in a very localised area, with the vast majority below tropical storm force (or gale force to you and me).